document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1206417>Question 1206417</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Question: Find an equation for a circle with center ( ―2, 3), tangent (touching at one point) to the y-axis.\r<BR>\n" );
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document.write( "My Attempt: <BR>\n" );
document.write( "Formula for a circle: (x-h)^2+(y-k)^2=r^2<BR>\n" );
document.write( "(x+2)^2+(y-3)^2=r^2<BR>\n" );
document.write( "Would this be the final equation? And if I am given a specific point that passes through the y-axis I would substitute that given ordered pair into x and y and solve for r^2, then replace it back into the original equation correct? <BR>\n" );
document.write( "For example: Center = (-2,3) passes through (3,7)<BR>\n" );
document.write( "(3+2)^2+(7-3)^2=r^2<BR>\n" );
document.write( "sqrt(41)=r<BR>\n" );
document.write( "Final equation = (x+2)^2+(y-3)^2=sqrt(41) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #843877 by </B><A HREF=/tutors/aboutme.mpl?userid=MathLover1><B>MathLover1(20855)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=MathLover1><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=MathLover1><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=843877\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> \r<BR>\n" );
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document.write( "Formula for a circle: \r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28x-h%29%5E2%2B%28y-k%29%5E2=r%5E2 ALIGN=MIDDLE  ALT=\"%28x-h%29%5E2%2B%28y-k%29%5E2=r%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" >.....center ( <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-2 ALIGN=MIDDLE  ALT=\"-2\"   DISABLED_style= \"max-width:90%; height:auto;\" >, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3 ALIGN=MIDDLE  ALT=\"3\"   DISABLED_style= \"max-width:90%; height:auto;\" >)\r<BR>\n" );
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document.write( "The circle is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=tangent ALIGN=MIDDLE  ALT=\"tangent\"   DISABLED_style= \"max-width:90%; height:auto;\" > to the <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y ALIGN=MIDDLE  ALT=\"y\"   DISABLED_style= \"max-width:90%; height:auto;\" >-axis (we know that tangent refers to a line that <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=touches ALIGN=MIDDLE  ALT=\"touches\"   DISABLED_style= \"max-width:90%; height:auto;\" > something at exactly one point, we want the circle to have a radius that will make it just big enough to reach the <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y ALIGN=MIDDLE  ALT=\"y\"   DISABLED_style= \"max-width:90%; height:auto;\" >-axis), hence its radius <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r=x-coordinate=-2 ALIGN=MIDDLE  ALT=\"r=x-coordinate=-2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28x%2B2%29%5E2%2B%28y-3%29%5E2=%28-2%29%5E2 ALIGN=MIDDLE  ALT=\"%28x%2B2%29%5E2%2B%28y-3%29%5E2=%28-2%29%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28x%2B2%29%5E2%2B%28y-3%29%5E2=4 ALIGN=MIDDLE  ALT=\"%28x%2B2%29%5E2%2B%28y-3%29%5E2=4\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+drawing%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C%0D%0Acircle%28-2%2C3%2C.12%29%2C+locate%28-2%2C3%2CC%28-2%2C3%29%29%2C%0D%0A%0D%0Agraph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C+3+-+sqrt%28-x%5E2-4x%29%2C+sqrt%28-x%5E2-4x%29%2B3%29%29+ ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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